So how do we know if the column is long or short? - We check for the slenderness ratio.
For short columns, you need to use Johnson's formula. However, that formula is applicable to only long columns. There's also a mixed case in which the combination of flexural and torsional load causes the structure to buckle, known as flexural-torsional buckling.Įuler's buckling formula helps estimate the critical load. The buckling can be due to flexural or torsional loads and is categorized as flexural and torsional buckling. The buckling induces instabilities in the structure causing it to fail. That is why the buckling load requires a separate consideration in the design and the stresses, as the failure due to buckling could occur before the stresses in the column satisfy the yield criterion. The buckling in a column depends on the elastic stiffness of the material rather than its load-bearing compressive strength.
The buckling causes a reduction in the axial stiffness of the column that results in displacement and rotations having catastrophic consequences. The load at which the member fails is known as the critical load, F c r i t F_ F cr i t or F F F. Buckling is a phenomenon under which a member can suddenly fail due to excessive compressive load.
